Repair works were undertaken on the Carlisle to Settle railway following a 500,000 tonne landslip in February 2016, closing the line near Armathwaite.
In February 2016, a 500,000 tonne landslip closed the Carlisle to Settle railway near Armathwaite. The damage occurred following Storm Desmond which devastated Cumbria and hit other parts of the UK in December 2015.
This site had a complicated history. It is located between two geological faults and during the construction of the railway in the late 1800s, a failure occurred which ‘pushed the river into the next Parish’. This historic landslide was ‘reactivated’, causing movement around 15 metres deep between the River Eden and the railway. The railway line is located 200 metres away from the
river and 60 metres above it.
The landslip resulted in large movements of the rail embankment and upside tracks. We designed a £23 million solution to provide a stable structure to allow the line to be reopened whilst the landslide continued to move. This involved an anchored pile wall which was ‘socketed’ into the ‘intact’ bedrock below the failure. We had 14 months to complete the task.
1,200m3
concrete poured
into the slab & wall
266
high strength piles
driven into bedrock
The repair works of this historic railway included:
• One mile of access roads
• 16,000 tonnes of spoil removed from the site
• The installation of 226 piles – around 4,040 metres
• A 75-metre-long, one-metre-thick reinforced concrete slab
• A retaining wall which was 95 metres long and 4 metres high
• 1,200m³ of concrete poured in the slab and wall
• 6,000 tonnes of backfill
• 490 metres of track reinstalled
• 2,400 metres of track re-aligned
• 3,000 tonnes of new ballast installed
• 226 piles installed
After careful consideration during the design stage of the project, a piling solution was chosen. Two rows of highstrength steel piles were filled with concrete and driven into the sloping bedrock, forming a corridor upon which a one metre-thick slab and retaining wall could be constructed to support the track.
This landslip had a big impact on the local community. We used engineering trains to remove the spoil from site, import stone and pile casings so that we removed HGV movements from the local roads where possible. During the main works, we implemented 24-hour working to ensure the railway could be handed back on time and on budget, ahead of a planned re-opening celebration with the Flying Scotsman passing over the site.
Eden Brows has been a hugely challenging job, as I saw for myself last year. I am impressed and grateful to the innovative team that led this work and to Story and the other contractors who helped make it happen. Well done to you all. A great railway team effort.
Network Rail
The project involved regrading approximately 280 metres of the embankment to enhance structural stability and improve rail safety.